The present invention relates to a device for monitoring sheet products, in particular printed products, transported in a transport device by means of clamps.
A method and a device for monitoring pairs of sheet products bearing identification information, each transported in a clamp of a transport device, are known from the Swiss patent application with the application number 01276/05. As they pass a monitoring point, the products are subjected to an opto-electronic check with an image recording device. The images of the identification information recorded in this way are compared with given calibration images in an electronic further processing device. As a result of this comparison it is possible to determine whether the clamp was carrying the predetermined products. In the event of an error, control signals can be transmitted to downline processing devices so that a separate treatment of clamps holding the wrong products can be initiated.
In order to ensure high reliability in the recording of the identification information, it is necessary that this information always passes in roughly the same positions during the recording. In the above-mentioned patent application, this is ensured in that the identification information is contained on edge sections of each product in a side edge area of the products that is firmly gripped by the clamp jaws of the clamp. As the image recording device has to be located relatively close to the passing clamps during the recording of the identification information, positioning and installation problems can occur with some clamp transport devices due to the limited space available. An object is therefore to provide an improved monitoring device that allows the number of sheet products transported in a clamp to be monitored in the simplest and most reliable manner possible.